U.S. patent application number 12/215067 was filed with the patent office on 2009-02-26 for automotive drive train and method for reducing chatter in the same.
This patent application is currently assigned to Luk Lamellen und Kupplungsbau Beteiligungs KG. Invention is credited to Boris Serebrennikov, Stefan Winkelmann.
Application Number | 20090054201 12/215067 |
Document ID | / |
Family ID | 37814486 |
Filed Date | 2009-02-26 |
United States Patent
Application |
20090054201 |
Kind Code |
A1 |
Winkelmann; Stefan ; et
al. |
February 26, 2009 |
Automotive drive train and method for reducing chatter in the
same
Abstract
The invention relates to a method for reducing chatter in
automotive drive train which comprises an internal combustion
engine as the drive and a clutch device. According to the method, a
rotating component of the drive train is driven by means of the
internal combustion engine and the speed of the component is
detected. Any chatter is also detected. When chatter occurs, an
electric motor is used to transmit a torque onto the rotating
component in order to actively dampen the chatter. The rotating
component is driven by the electric motor for any chatter component
at which the speed of the rotating component decreases and the
rotating component is slowed down by the electric motor for any
chatter component at which the speed of the rotating component
increases.
Inventors: |
Winkelmann; Stefan; (Buehl,
DE) ; Serebrennikov; Boris; (Baden-Baden,
DE) |
Correspondence
Address: |
Davidson, Davidson & Kappel, LLC
485 7th Avenue, 14th Floor
New York
NY
10018
US
|
Assignee: |
Luk Lamellen und Kupplungsbau
Beteiligungs KG
Buehl
DE
|
Family ID: |
37814486 |
Appl. No.: |
12/215067 |
Filed: |
June 24, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
PCT/DE2006/002101 |
Nov 29, 2006 |
|
|
|
12215067 |
|
|
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Current U.S.
Class: |
477/5 ;
180/65.265; 903/902 |
Current CPC
Class: |
F16H 2200/0052 20130101;
B60L 15/2054 20130101; F16H 3/006 20130101; Y02T 10/70 20130101;
B60W 10/08 20130101; B60L 50/16 20190201; F16H 3/093 20130101; B60K
6/48 20130101; B60Y 2400/428 20130101; B60L 2240/421 20130101; B60W
30/20 20130101; Y02T 10/64 20130101; B60L 2240/486 20130101; B60L
15/20 20130101; B60L 2240/423 20130101; Y02T 10/72 20130101; B60L
2270/145 20130101; B60L 2240/443 20130101; B60W 10/11 20130101;
Y02T 10/7072 20130101; Y10T 477/26 20150115; Y02T 10/62 20130101;
B60L 2240/441 20130101 |
Class at
Publication: |
477/5 ;
180/65.265; 903/902 |
International
Class: |
B60W 30/20 20060101
B60W030/20; B60W 20/00 20060101 B60W020/00; B60K 6/20 20071001
B60K006/20 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 24, 2005 |
DE |
10 2005 062 309.3 |
Claims
1-9. (canceled)
10. A method for reducing chatter in a motor vehicle power train
that has a combustion engine as a drive and has a clutch device,
wherein a rotating component of the power train is driven by the
combustion engine and a speed of rotation of the rotating component
is detected, and wherein the presence of chatter is detected, the
method comprising, when chatter occurs: actively damping the
chatter for a chatter component by transmitting a torque to the
rotating component via an electric motor, so that, when the speed
of the rotating component is decreasing, the rotating component is
driven by the electric motor, and, when the speed of the rotating
component is increasing, the rotating component is retarded by the
electric motor.
11. The method as recited in claim 10 wherein the rotating
component is an input shaft of a shift transmission, and further
comprising measuring a rotational speed signal for the first or
second input shaft to detect the speed of rotation.
12. The method as recited in claim 11 further comprising providing
a control signal for the torque of the electric motor, a signal for
the chatter component included in the rotational speed signal being
generated through high-pass filtering of the rotation speed signal,
forming a differential signal from the control signal and the
signal for the chatter component, and setting the torque of the
electric depending on the differential signal.
13. The method as recited in claim 12 wherein the torque of the
electric motor is set in proportion to an amplitude of the
differential signal.
14. The method as recited in claim 12 further comprising
determining a mean acceleration of the rotating component, and
choosing the control signal so that the acceleration of the
electric motor conforms to the mean acceleration of the rotating
component.
15. The method as recited in claim 11 wherein the motor vehicle
power train has the combustion engine, the electric motor, the
clutch device and a parallel shift transmission with a drive part
and a first input shaft as well as a second input shaft, and the
clutch device has a first clutch to connect a drive part to the
first input shaft and a second clutch to connect a drive part to
the second input shaft, the method including: a) disengaging the
first and second clutches to a disengaged position in which the
first input shaft and the second input shaft are separated from the
drive part, b) for a drive-off procedure, setting the parallel
shift transmission so that the first input shaft has a drive
connection with an output shaft of the parallel shift transmission
by way of a first gear, and the second input shaft is connected by
way of a second gear, c) engaging the first clutch at least far
enough so that the first clutch can transmit a torque, d) detecting
whether chatter is present, e) if chatter is present, transmitting
a torque to the second input shaft by the electric motor-in such a
way that with the chatter component where the speed of the second
input shaft is decreasing, the shaft is driven by the electric
motor, and with the chatter component where the speed of the second
input shaft is increasing, the shaft is retarded by the electric
motor, f) continuing the procedure with step d).
16. The method as recited in claim 15 wherein after steps c), d)
and/or e) checking whether a drive-off process has ended, and steps
d), e) and/or f) are carried out only if the drive-off process has
not ended.
17. A motor vehicle power train comprising: a combustion engine as
a drive; a clutch device; and a device for registering the speed of
rotation of a rotating component of the power train, wherein the
device for detecting the speed of rotation is connected to a
control and/or a regulating device, the motor vehicle power train
having an electric motor-as an auxiliary drive connected to the
control and/or regulating device through an actuating device, the
control and/or regulating device being designed so that with a
chatter component where a speed of rotation is decreasing a
rotating component is driven by the electric motor, and with the
chatter component where the speed of rotation of the rotating
component is increasing, the rotating component is retarded by the
electric motor.
18. The motor vehicle power train as recited in claim 17 wherein
the rotating component is an input shaft of a shift transmission,
and the device for detecting the speed of rotation is a rotational
speed sensor.
19. The motor vehicle power train as recited in claim 18 wherein
the shift transmission is a parallel shift transmission.
Description
[0001] This is a continuation of prior International Application
PCT/DE2006/002101, filed Nov. 29, 2006.
[0002] The invention relates to a method for reducing chatter in a
motor vehicle power train that has a combustion engine as drive and
a clutch device, wherein a rotating component of the power train is
driven by means of the combustion engine and the speed of rotation
of the component is detected, and wherein the presence of chatter
is detected. The invention also relates to a motor vehicle power
train that has a combustion engine as drive, a clutch device and a
device for registering the speed of rotation of a rotating
component of the power train, wherein the device for detecting the
speed of rotation is connected to a control and/or regulating
device.
BACKGROUND
[0003] Such a method and such a motor vehicle power train, in which
chatter induced during the slippage phase of a clutch itself occurs
in the power train, are known from DE 102 44 026 A1. The chatter is
caused by a negative friction coefficient gradient of the clutch,
which makes the damping in the power train negative. The vibrations
are converted by the drive wheels of the motor vehicle into
longitudinal vibrations, and are experienced as unpleasant by the
vehicle occupants. To reduce the amplitude of the chatter, a
transmission brake situated in the power train acts on a rotating
component in the vehicle power train in such a way that the rotary
motion of this component is continuously or periodically retarded.
The transmission brake only makes a limited reduction of the
chatter possible, however.
SUMMARY OF THE INVENTION
[0004] An object of the present invention provides a method and a
device of the type named at the beginning, which makes effective
attenuation of the chatter possible.
[0005] In accordance with an embodiment of the present invention,
the invention provides that when chatter occurs, to actively damp
the chatter a torque is transmitted to the rotating component by
means of an electric motor in such a way that for a chatter
component where the speed of the rotating component is decreasing
the rotating component is driven by means of the electric motor,
and for a chatter component where the speed of the rotating
component is increasing the rotating component is retarded by means
of the electric motor.
[0006] Thus the torque of the electric motor may be modulated so
that the chatter is actively damped. The amplitude of the chatter
oscillations may be effectively attenuated in both directions. This
method can be used to reduce both chatter that is caused by
negative friction coefficient gradients of the clutch and chatter
that occurs due to geometric irregularities. In an advantageous
manner, in addition to damping the chatter, the electric motor can
also be used as a drive motor for the motor vehicle power train, in
addition to and/or instead of the combustion engine. The combustion
engine can then be dimensioned correspondingly smaller. Compared to
a combustion engine without an electric motor, a hybrid drive of
this sort may makes a significant reduction in fuel consumption
possible, since when coasting the combustion engine is uncoupled
from the drive wheels of the motor vehicle power train, and the
deceleration energy may be converted by means of the electric motor
into electrical energy and may be temporarily stored for example in
a rechargeable battery.
[0007] In an expedient embodiment of the invention, the rotating
component may be an input shaft of a shift transmission, in
particular a parallel shift transmission, where a rotation speed
signal for the input shaft may be measured to detect the speed of
rotation. The rotation speed signal is preferably measured
inductively.
[0008] It is beneficial, when a control signal for the torque of
the electric motor is provided, if a signal for a chatter component
included in the rotational speed signal is preferably generated
through high-pass filtering of the rotation speed signal, if a
differential signal is formed from the control signal and the
signal for the chatter component, and the torque of the electric
motor is set depending on the differential signal. The chatter can
then be attenuated even more effectively.
[0009] Here the torque of the electric motor is preferably set in
proportion to the amplitude of the differential signal whereby
using a parameterizable proportionality factor may be
implemented.
[0010] In a preferred embodiment of the invention the mean
acceleration of the rotating component is determined, with the
control signal being chosen so that the acceleration of the
electric motor conforms to the mean acceleration of the rotating
component. That makes it unnecessary for the mass of the electric
motor to be accelerated by the combustion engine.
[0011] A preferred design of the invention may include the motor
vehicle power train having a combustion engine, an electric motor,
a clutch device and a parallel shift transmission with a drive part
and a first and a second input shaft and that the clutch device has
a first clutch to connect the drive part to the first input shaft
and a second clutch to connect the drive part to the second input
shaft, comprising the following steps:
[0012] the clutches are brought to a disengaged position in which
the first input shaft and the second input shaft are separated from
the drive part,
[0013] for a drive-off procedure, the parallel shift transmission
is set so that the first input shaft 17a has a drive connection
with an output shaft 22 of the parallel shift transmission by way
of a first gear, and the second transmission shaft 17b is connected
by way of a second gear,
[0014] the first clutch K1 is engaged at least far enough so that
it can transmit a torque,
[0015] the system detects whether chatter is present,
[0016] if chatter is present, the electric motor 11 is used to
transmit a torque to the second input shaft 17b in such a way that
with a chatter component where the speed of the second input shaft
17b is decreasing, the shaft is driven by means of the electric
motor 1, and with a chatter component where the speed of the second
input shaft 17b is increasing, the shaft is retarded by means of
the electric motor 11,
[0017] the procedure continues with step d). [0018] During the
drive-off procedure the electric motor may thus be connected by way
of the second gear and the second transmission shaft to the output
shaft of the parallel shift transmission, so that the electric
motor can introduce a torque into the output shaft of the parallel
shift transmission whose pattern may be chosen so that the chatter
may be actively attenuated.
[0019] In a preferred embodiment of the invention, after steps c),
d) and/or e) the system checks whether the drive-off process has
ended, and steps d), e) and/or f) are carried out only if the
drive-off process has not ended. Thus the compensation for chatter
may be blocked outside of the drive-off process, in order to avoid
unnecessary actuation of the electric motor.
[0020] In regard to the motor vehicle power train, the problem
named earlier may be solved by the motor vehicle power train having
an electric motor as auxiliary drive, which is connected to the
control and/or regulating device through an actuating device, and
by the control and/or regulating device being designed so that with
a chatter component where the speed of rotation is decreasing the
rotating component may be driven by means of the electric motor,
and with a chatter component where the speed of rotation of the
rotating component is increasing, the rotating component may be
retarded by means of the electric motor.
[0021] By means of the electric motor, chatter that occurs at the
clutch device can be reduced actively by overlaying a torque that
is modulated contrary to the chatter. The hybrid drive made from
the combustion engine and the electric motor may also enables
fuel-saving operation of the motor vehicle power train.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] An exemplary embodiment of the invention will be explained
in greater detail below on the basis of the drawing. The figures
show the following:
[0023] FIG. 1: a schematic partial depiction of a motor vehicle
power train having a parallel shift transmission, wherein a first
clutch is engaged and a second clutch is disengaged, and
[0024] FIG. 2: a depiction similar to FIG. 1, but wherein the first
clutch is disengaged and the second clutch is engaged.
DETAILED DESCRIPTION
[0025] A motor vehicle power train shown schematically in FIGS. 1
and 2 has a hybrid drive with a combustion engine 10 in the form of
a reciprocating piston engine and an electric motor 11 designed as
a starter generator as its drive. The combustion engine 10 has a
crankshaft 12 on which reciprocating pistons 13 are mounted through
connecting rods; the reciprocating pistons are situated so that
they can move away from and toward the crankshaft 12 in cylinders
of an engine block in a known manner. On the engine block a
cylinder head is provided, which has intake and outlet valves that
are actuatable by means of a control device which is not shown in
further detail in the drawing. The reciprocating pistons 13, the
cylinder head and the intake and outlet valves delimit combustion
chambers, in which a fuel-air mixture can be ignited.
[0026] The crankshaft 12 is drive-connected with a flywheel 14,
which has a ring gear that meshes with two gear wheels 15a, 15b
that are situated at the circumference of the ring gear and offset
from each other. Each of these drives a clutch plate 16a. A first
clutch plate 16a of a first clutch K1 is situated axially relative
to a first gear wheel 15a, and a first clutch plate 16a of a second
clutch K2 is situated axially relative to a second gear wheel 15b.
Assigned to each first clutch plate 16a is a second clutch plate
16b. The respective first and second clutch plates 16a, 16b that
are assigned to each other can be brought into a disengaged and an
engaged position. In the disengaged position the first and second
clutch plates 16a, 16b are at a distance from each other axially,
and in the engaged position the clutch plates 16a, 16b are in
contact with each other and frictionally engaged.
[0027] The second clutch plate 16b of the first clutch K1 is
drive-connected with a first transmission input shaft 17a, and the
second clutch plate 16b of the second clutch K2 is drive-connected
with a second transmission input shaft 17b of a parallel shift
transmission. Situated on the transmission input shafts 17a, 17b
are first transmission gears 18a, 18b, which can be connected by
means of a shifting apparatus (not shown in further detail in the
drawing) in a rotationally fixed connection to the transmission
input shaft 17a, 17b assigned to them, to change the transmission
ratio. Synchronizer rings 19 are provided to synchronize the first
transmission gears 18a, 18b with the respective transmission input
shafts 17a, 17b assigned to them. The first transmission gears 18a
situated on the first transmission input shaft 17a are assigned to
reverse gear R and to forward gears 1, 3 and 5, and the first
transmission gears 18a situated on the second transmission input
shaft 17b are assigned to forward gears 2, 4 and 6.
[0028] The second input shaft 17b is drive-connected with the rotor
of an electric motor 11, the stator of which is connected to the
motor block in a rotationally fixed connection. A winding of the
electric motor 11 is connected to a rechargeable battery through an
actuating device 20.
[0029] The first transmission gear wheels 18a, 18b mesh with second
transmission gear wheels 21, which are situated on an output shaft
22 of the parallel shift transmission and are rigidly connected to
that shaft. The output shaft 22 is drive-connected through a
differential to drive wheels (not shown in further detail in the
drawing) of the power train. The first transmission gear wheels
18a, 18b and the second transmission gear wheels 21 have different
diameters.
[0030] To start the combustion engine 10, the first transmission
gear wheels 18b situated on the second input shaft 17b are
disengaged from the input shaft 17b. If the first transmission gear
wheels 18b are already disengaged from the second input shaft 17b,
this step can be omitted.
[0031] In addition, the first clutch K1 is brought to the
disengaged position and the second clutch K2 to the engaged
position. If the clutches K1, K2 are already in the indicated
position, this step can be omitted. Alternatively, the first clutch
K1 can be brought to the engaged position and the first
transmission gear wheels 18a disengaged from the first input shaft
17a.
[0032] Then the combustion engine 10 will be driven by means of the
electric motor 11 in order to start it. As that occurs, the
electric motor 11 transmits a drive torque to the second drive
shaft, which is transmitted through the second clutch K2 to the
crankshaft 12.
[0033] With first clutch K1 disengaged, the parallel shift
transmission is set so that the first transmission shaft 17a is
drive-connected through the first gear with the output shaft 22 of
the parallel shift transmission. Furthermore, with second clutch K2
disengaged, the parallel shift transmission is set so that the
second transmission shaft 17b is connected through the second gear
with the output shaft 22.
[0034] Then the first clutch K1 is slowly engaged to start the
motor vehicle in motion, so that the combustion engine 10 transmits
a drive torque to the drive wheels through first clutch K1, first
input shaft 17a, a first transmission gear wheel 18a, a second
transmission gear wheel 21 and output shaft 22. Clutch K2 continues
to be disengaged (see FIG. 1).
[0035] At the same time, the system detects whether chatter is
present. To that end, for example, a rotational speed signal
N.sub.Ge for the first input shaft 17a can be measured, and any
vibrating component that may be present can be filtered out of the
rotational speed signal N.sub.Ge and then compared with a
limit.
[0036] If chatter is present, the electric motor 11 is used to
transmit a torque to the second input shaft 17b and from there
through the second gear to the output shaft 22 in such a way that
with a chatter component where the speed of the first input shaft
17a is decreasing, the shaft is driven by means of the electric
motor 11, and with a chatter component where the speed of the first
input shaft 17a is increasing, the shaft is retarded by means of
the electric motor 11. To that end, a control signal M.sub.control
is provided for the torque M.sub.e-machine of the electric motor
11, and a signal is produced for a chatter component included in
the rotational speed signal N.sub.Ge by filtering the rotational
speed signal N.sub.Ge. The control signal M.sub.control is chosen
so that the acceleration of the electric motor 11 conforms to the
mean acceleration of the second input shaft 17b. That makes it
unnecessary for the mass of the electric motor 11 to be accelerated
by the combustion engine 10. A differential signal is formed from
the control signal and the signal for the chatter component, and
the torque of the electric motor 11 is set depending on the
differential signal:
M.sub.e-machine=M.sub.control-k*(N.sub.Ge-N.sub.G-filt)
[0037] N.sub.Ge-filt is produced here by low-pass filtering the
rotational speed signal N.sub.Ge. The value k stands for a
proportionality factor. The corresponding torque is transmitted
through the second gear to the output shaft 22, and from there
through the first gear to the first input shaft 17a.
[0038] A check is then performed to determine whether the drive-off
process has ended. The velocity of the vehicle can be measured to
that end and compared to a limit. Instead of the velocity, however,
the rotational speed of the first input shaft can also be measured
and compared to the limit.
[0039] If the drive-off process has not yet ended, the system
checks whether the chatter has subsided. To that end, the vibrating
component of the rotational speed signal is newly determined and
compared to the limit. If the chatter has not subsided, it
continues to be damped by means of the electric motor 11, while the
procedural steps described above are run through again.
[0040] If no chatter is present, the system checks whether the
drive-off process has ended. If not, the system again checks
whether chatter is present, in order to compensate for it by means
of the electric motor 11 if necessary. The system just described
can be employed accordingly when starting out in reverse gear
R.
[0041] As can be seen from FIG. 2, it is also possible to start out
in second gear. With second clutch K2 disengaged, the parallel
shift transmission is set so that the second transmission shaft 17b
is drive-connected through the second gear with the output shaft 22
of the parallel shift transmission. Furthermore, the first clutch
K1 is disengaged and/or the first gear wheels are disengaged from
the first transmission shaft 17a.
[0042] Then the second clutch K2 is slowly engaged to start the
motor vehicle in motion, so that the combustion engine 10 transmits
a drive torque to the drive wheels through second clutch K2, second
input shaft 17b, transmission gear wheel 18b for the second gear, a
second transmission gear wheel 21 and output shaft 22. Clutch K1
continues to be disengaged (see FIG. 2).
[0043] Now the system detects whether chatter is present. To that
end a rotational speed signal for the second input shaft 17b is
measured, and any chatter component present is filtered out of the
rotational speed signal and then compared to a limit.
[0044] If chatter is present, the electric motor 11 is used to
transmit a torque to the second input shaft 17b and from there
through the second gear to the output shaft 22 in such a way that
with a chatter component where the speed of the second input shaft
17b is decreasing, the shaft is driven by means of the electric
motor 11, and with a chatter component where the speed of the
second input shaft 17b is increasing, the shaft is retarded by
means of the electric motor 11. The torque M.sub.e-machine of the
electric motor 11 is determined according to the equation stated
above from the control signal M.sub.control, the rotational speed
signal N.sub.Ge for the second input shaft 17b and the
proportionality factor k. Otherwise the procedural steps set forth
for FIG. 1 are utilized accordingly.
[0045] It should also be mentioned that the electric motor 11 can
also be situated axially relative to the crankshaft 12.
REFERENCE LABELS
[0046] 10 combustion engine [0047] 11 electric motor [0048] 12
crankshaft [0049] 13 reciprocating piston [0050] 14 flywheel [0051]
15a first gear wheel [0052] 15b second gear wheel [0053] 16a first
clutch plate [0054] 16b second clutch plate [0055] 17a first input
shaft [0056] 17b second input shaft [0057] 18a first transmission
gear wheel [0058] 18b first transmission gear wheel [0059] 19
synchronizer ring [0060] 20 actuating device [0061] 21 second
transmission gear wheel [0062] 22 output shaft [0063] K1 first
clutch [0064] K2 second clutch
* * * * *